hgprieto

Syntax >>> LEVENBERG: lambda Parent Command >> CONVERGE Subcommand – Description This command sets the initial value of the Levenberg parameter lambda (default: 0.001). During the optimization process (see command >>> LEVENBERG-MARQUARDT>) the Levenberg parameter is divided by the Marquardt parameter nue (see command >>> MARQUARDT) after each successful iteration, and is multiplied by nue […]

Syntax >>> ITERATION: max_iter Parent Command >> CONVERGE Subcommand – Description This command sets the maximum number of iTOUGH2 iterations to max_iter. If using the Levenberg-Marquardt minimization algorithm, an iTOUGH2 iteration consists of a number of TOUGH2 simulations and includes the following steps: (1) solution of the forward problem; (2) evaluation of the Jacobian matrix

Syntax >>> INPUT Parent Command >> CONVERGE Subcommand – Description This command makes iTOUGH2 stop immediately after the TOUGH2 and iTOUGH2 input files have been read and checked for consistency. This is useful to check input before time consuming simulations are invoked, or in combination with LIST, HELP, and >>> INDEX. Example > COMPUTATION >>

Syntax >>> INCOMPLETE: max_incomplete Parent Command >> CONVERGE   Subcommand – Description A successful iTOUGH2 run is based on the robustness and stability of the underlying TOUGH2 simulation. It is therefore imperative to develop a TOUGH2 model that is capable of completing the desired simulation for a variety of parameter combinations. The simulation must reach

Syntax >>> GOODNESS-OF-FIT Parent Command >> CONVERGE Subcommand – Description Optimization stops if the goodness-of-fit criterion is met, i.e., if the estimated error variance is less than 1.0. Example > COMPUTATION >> STOP >>> use GOODNESS-OF-FIT convergence criterion <<< << See Also –

Syntax >>> FORWARD or >>> DIRECT Parent Command >> CONVERGE or >> OPTION   Subcommand – Description This command allows one TOUGH2 simulation to be performed in order to solve the forward problem. It is advantageous to perform a single TOUGH2 simulation before invoking more expensive inversions. The result from the forward run can be

Syntax >>> DIRECT Parent Command >> OPTION or >> CONVERGE   Subcommand –   Description (synonym for command >>> FORWARD (o)) Example (see command >>> FORWARD (o)) See Also >>> FORWARD (o)

Syntax >>> DELTFACT: deltfact Parent Command >> CONVERGE   Subcommand –   Description In TOUGH2, time step size can be controlled in various ways (see Pruess [1987] for a description of input variables DELTEN, DLT, DELTMX, NOITE, REDLT, and MOP(16)). The time step is also automatically adjusted in order for the simulation time to land

Syntax >>> CONSECUTIVE: max_iter1 Parent Command >> CONVERGE   Subcommand –   Description By default, TOUGH2 simulations are stopped if 10 consecutive time steps converge with a single Newton-Raphson iteration because no update of primary variables occurs. This command allows changing the maximum number of allowable time steps with ITER=1 to max_iter1. Consecutive time steps

Syntax >>> ADJUST Parent Command >> CONVERGE   Subcommand –   Description The initial time step size is provided through TOUGH2 variable DELTEN or DLT(1), usually followed by automatic time stepping (see TOUGH2 variables MOP(16) and REDLT). The initial time step may be too big (i.e., is automatically reduced by TOUGH2) or too small (i.e.,